this originally came from MixingBowl.com - I have modified the original with regard to flavor(s) & procedural points. see expanded notes on flavorings below.

Fair Warning: this is not a lo-cal, lo-fat thing.

shopping list:
1 can of dark cherries in heavy syrup (about 16 ounces by weight)
one chocolate crumb pre-made pie crust.
two cups heavy whipping cream
four tablespoons of sugar.
two ounces by weight of semi-sweet bakers chocolate
small chunk of bittersweet chocolate for shaved garnish
flavorings
one orange (I've made it without the orange, works . . .)

reduce cherry syrup about 50% in a shallow pan with a thick slice of orange.
after syrup is simmering, I use a fork to smish out the orange flavor.

while that is happening, using a double boiler method, start melting the semi-sweet chocolate.

while that's starting, whip up one cup of heavy whipping cream to stiff, adding 2 tablespoons of sugar.

as the chocolate begins to melt, and as the syrup is reduced, add two tablespoons of reduced syrup to the chocolate (there will be left over syrup)
this will speed up the melting.
add flavoring (see below)

fold in the melted chocolate to the whipped cream
put the drained cherries into the pie shell
pour in the whipped cream/chocolate mix
smush down the whipped filling to fill in the voids between the cherries.
looks like:

the future of your pie....
the original recipe indicates whipping the second cup of cream and applying that as a topping in immediate sequence. I have found the "fresh" filling very soft and immediately applying the topping rather tricky, so my modification is to put in the filling cream and refrigerate four hrs to overnight before applying the topping.

going over the topping:
as close to service time as practical,
whip the second cup of cream with 2 tbsps of sugar + flavorings
apply to pie
garnish with shaved bitter sweet chocolate (or other)
other: whole cherry(ies) - either one per center or one per perimeter slice
also: see below
or also, all of the above.
looks like:
flavorings:
the original recipe calls for 1 tbsp of Kirsch in the filling mix plus 1 tbsp of Kirsch in the topping whipped cream. a bit like Death by Triple Chocolate. too much cherry, imho.
for the filling cream I prefer 1/2 tsp of almond extract. almond & cherry are very complimentary.
for the topping cream I have used:
1/4 tsp almond extract (works . . .)
1 tbsp rum (okay - need a very flavorful but not dark rum)
my favorite
1/4 tsp spearmint extract - with a garnish of fresh spearmint sprig if you gotta 'um.
careful with the extracts - a little bit goes a long way and can overpower the basic flavor.